Latch devices are well known for holding the doors of trucks, trailers, and other vehicles in open condition. Such a latch commonly consists of a latch bar pivotally mounted on a truck body with an enlarged free end receivable in the recess of a door-mounted keeper capable of being swung into close proximity to the latch bar. A need nevertheless exists for a latch assembly which is simple and reliable in structure and operation and which includes some means for insuring that the latch bar will not become accidentally unlatched as the vehicle moves into position adjacent a loading platform, backs through an alleyway, or is shifted relative to any building or object. Should the latch release during such operations, there is a substantial risk that the door will engage the platform, building, or other object and will become crushed, strained, or otherwise damaged. Furthermore, should such contact occur, it is evident that the object engaged by the door might suffer substantial damage.
The following patents are illustrative of the prior art: U.S. Pat Nos. 3,224,802, 3,625,557, 3,063,745, 3,302,966, 2,802,682 and 2,475,223.